More ligands at the receptor

More ligands at the receptor

After drug treatment, a receptor in the body usually has more than 1 ligand which is able to bind: the endogenous ligand and the administered drug.

For pharmacology, the development of (partial) agonists and antagonists for a specific receptor is challenging.

A receptor antagonist does not provoke a biological response itself upon binding to a receptor, but blocks binding and thus response of

an endogenous ligand. Antagonists have affinity but no efficacy for the receptor. The majority of drug antagonists achieve their potency by competing with endogenous ligands at binding sites on receptors.

Also check here for short animations of different ligands (all kinds of ligands in this section).